CN103293985B - Zero consumption standby circuit - Google Patents

Abstract

The invention discloses a kind of Zero consumption standby circuit, relate to household electrical appliance technical field, this circuit comprises: single-chip microcomputer, key press detecting circuit, strong electrical control circuit, described single-chip microcomputer is connected with described key press detecting circuit and strong electrical control circuit respectively, for receiving the forceful electric power button signal that described key press detecting circuit detects, and trigger connection or the disconnection that described strong electrical control circuit controls forceful electric power and electric equipment, described single-chip microcomputer connects light current power supply, described key press detecting circuit comprises strong and weak electricity spacer assembly, flows into single-chip microcomputer for isolating forceful electric power.Zero consumption standby circuit of the present invention not only achieves standby zero-power-consumption, and avoids potential safety hazard, enhances the security of circuit.

Description

Zero Power Standby Circuit

technical field

The invention relates to the technical field of household appliances, in particular to a zero-power consumption standby circuit.

Background technique

At present, the country's requirements for the standby power consumption of household appliances are constantly improving, so various methods for reducing standby power consumption have emerged, such as low-power consumption devices, control methods and so on. For example, the washing machine first introduced a zero-power consumption control method, because most of the washing machine program controllers were designed in a floating way. As shown in Figure 1, when no button is pressed, the whole circuit is not charged. When SW312 is pressed, the circuit has current, and the single chip microcomputer works. By controlling K1 to close, when the button SW312 is lifted, the circuit still has power. When the program finishes running or the button input terminal detects that SW312 is pressed again, K1 is disconnected. At this time, the circuit is powered off, and the entire circuit is in zero power consumption.

The design of the above zero-power consumption circuit is designed for the floating mode. Although it can achieve zero power consumption in standby mode, the safety is not high. The disadvantages of this circuit are:

1. In order to meet the voltage-to-ground design, the weak current +5V and the strong current are connected together, as shown in Figure 1, the L' terminal is connected after K1 is closed, so that when there is power, the entire circuit will have strong current. The use of some touch-type buttons on home appliances will lead to electric shock, which is prone to safety hazards.

2. When the two ends L and L' of the button SW312 are connected, they are directly connected to the single-chip microcomputer. If the two ends L and L' are wrongly connected reversely, the single-chip microcomputer and the entire circuit will be damaged.

Contents of the invention

(1) Technical problems to be solved

The technical problem to be solved by the invention is: how to realize a highly safe zero-power consumption standby circuit.

(2) Technical solution

In order to solve the above-mentioned technical problems, the present invention provides a zero-power standby circuit, including: a single-chip microcomputer, a key detection circuit, and a strong current control circuit, and the single-chip microcomputer is respectively connected with the key detection circuit and the strong current control circuit for use in Receive the strong power button signal detected by the key detection circuit, and trigger the strong power control circuit to control the connection or disconnection of the strong power and electrical equipment, the single-chip microcomputer is connected to a weak power supply, and the key detection circuit includes a strong The isolation device is used to isolate the strong current from entering the microcontroller.

Wherein, the key detection circuit further includes a strong power button, the strong power button is connected to the strong and weak current isolation device, and the strong and weak current isolation device is connected to the single-chip microcomputer.

Wherein, the strong and weak electric isolation device includes a photocoupler, the anode end of the light-emitting diode of the photocoupler is connected to the strong electric button, the cathode end of the light-emitting diode is connected to the neutral line of the strong electricity, and the photosensitive The emitter terminal of the triode is grounded, and the collector terminal of the photosensitive triode is connected with the single-chip microcomputer.

Wherein, the strong and weak electrical isolation device further includes: a first resistor, a second resistor, a first diode and a capacitor, and the first resistor, the first diode and the capacitor are connected in parallel to the light emitting diode of the photocoupler. Between the anode terminal and the cathode terminal of the diode, the cathode terminal of the light emitting diode of the photocoupler is connected to the neutral line of strong electricity through the second resistor.

Wherein, the strong current control circuit includes: a control sub-circuit and a relay, the control sub-circuit is respectively connected to the single-chip microcomputer and the relay, and is used to control the on-off of the contact switch of the relay to connect or disconnect the high-power and electrical appliances. Device connection.

Wherein, the control sub-circuit includes: a triode, a third resistor, a fourth resistor and a second diode, the base of the triode is connected to the single-chip microcomputer through the fourth resistor, the emitter is grounded, and the third resistor is connected to the Between the base and the emitter of the triode, the second diode is connected to both ends of the relay, and the anode is connected to the collector of the triode, and the cathode is connected to the power supply of the relay.

(3) Beneficial effects

The zero-power consumption standby circuit of the present invention adopts a strong and weak current isolation device to isolate the strong current from directly flowing into the single-chip microcomputer, thereby ensuring the safety of the single-chip microcomputer and the entire circuit; after the switch of the relay is closed, the strong current is no longer directly connected to the weak current, thereby avoiding potential safety hazards. Enhanced circuit security.

Description of drawings

Fig. 1 is a kind of zero power consumption stand-by circuit diagram of prior art and the connection diagram with home appliance power supply;

FIG. 2 is a zero-power standby circuit diagram of an embodiment of the present invention;

FIG. 3 is a connection circuit diagram of the zero-power standby circuit in FIG. 2 and the power supply of the home appliance.

detailed description

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

As shown in Figure 2, the zero-power standby circuit of this embodiment includes: a single-chip microcomputer C, a key detection circuit A, and a strong current control circuit B, and the single-chip microcomputer C is respectively connected with the key detection circuit A and the strong current control circuit B for receiving The key detection circuit A detects the signal of the strong power button SW1, and triggers the strong power control circuit B to control the connection or disconnection of the strong power with the electrical equipment. The single-chip microcomputer C is connected to a weak power supply (5V), and the button detection circuit A includes a strong and weak current isolation device for isolating strong current from entering the single-chip microcomputer C.

In this embodiment, the button detection circuit A includes: a strong power button SW1 and a strong and weak current isolation device, the strong and weak current isolation device includes a photocoupler IC1, the strong power button SW1 is connected to the photocoupler IC1, and the photocoupler IC1 is connected to the single-chip microcomputer C . Specifically, the anode of the light-emitting diode of the photocoupler IC1 is connected to the strong power button SW1, the cathode of the light-emitting diode of the photocoupler IC1 is connected to the neutral line N of the strong electricity, and the collector of the phototransistor of the photocoupler IC1 is connected to the microcontroller C. The emitter end of the phototransistor of the photocoupler IC1 is grounded. Among them, the collector terminal of the phototransistor of the photocoupler IC1 is usually connected to the port I/O1 of the microcontroller C through the pull-up resistor R4 and the resistor R5. When the photocoupler IC1 is turned on and off, the level of the port I/O1 of the microcontroller C changes accordingly. . The function of R4 is to make the port I/O1 of the single-chip microcomputer C be high level when the photocoupler IC1 is not conducting, and it is low level when it is conducting; the function of R5 is to protect the port I/O1 of the single-chip microcomputer C, and R5 also You don't need to.

Preferably, the strong and weak electrical isolation device further includes some auxiliary components: a resistor R3, a resistor R2, a diode D2 and a capacitor C1. The resistor R3, the diode D2 and the capacitor C1 are connected in parallel between the first terminal and the second terminal of the photocoupler IC1, and the second terminal of the photocoupler IC1 is connected to the neutral line N through the resistor R2. R3 and C1 form a resistance-capacitance absorption circuit, which can play a protective role when SW1 switches; the function of D2 is to protect IC1 and prevent damage to IC1 from overvoltage; R2 is a selection power resistor, which must meet the requirements of Optocoupler IC1 conduction and its own power requirements.

In this embodiment, the strong current control circuit B includes: a control sub-circuit and a relay K1, the control sub-circuit is respectively connected to the single-chip microcomputer C and the relay K1, and is used to control the on-off of the contact switch of the relay K1 to turn on or off the high-power Connection to electrical equipment.

Specifically, the control sub-circuit includes: transistor N1, resistor R6, resistor R7 and diode D1, the base of the transistor N1 is connected to the port I/O2 of the microcontroller C through the resistor R7, the emitter is grounded, and the resistor R6 is connected to the terminal of the transistor N1. between base and emitter. The diode D1 is connected to both ends of the relay K1, and the anode is connected to the collector of the triode N1, and the cathode is connected to the power supply (12V) of the relay K1. When the port I/O2 of the microcontroller outputs a low level, the N1 transistor is not conducting, and the control coil of the relay K1 does not work, so the relay contact cannot be closed and is in the disconnected state; when the port I/O2 of the microcontroller outputs a high level, the N1 conduction On, the coil at the control end of the relay K1 is energized to work, and the relay contacts are closed, which is in a closed state.

As shown in FIG. 3 , it is a connection diagram between the zero-power standby circuit and the power supply of household appliances in this embodiment. The working principle of the zero-power standby circuit is as follows:

The live line L (or the neutral line N) is connected to the strong electric button and the relay. In this embodiment, it is connected to the live line L, and the normal operation and standby zero power consumption are realized through the operation of the strong electric button SW1 and the control of the relay K1 .

After connecting the power cord of the home appliance to the power socket, if no operation is performed, the strong current only exists on the lead wire, and no strong current enters the transformer circuit, so the entire single-chip program controller is in a power-off state, basically realizing zero. power consumption. When SW1 in A is pressed for the first time, L and L' are turned on through the button (L and L' in A and B are connected). At this time, the strong current is connected to the power supply of household appliances. There are three ways to control the closing of K1. One is to directly control the port I/O2 of the microcontroller to output a high level signal when the system is first powered on. The control circuit controls the closing of K1; After leveling, output a high-level signal to the strong current control circuit to control K1 to close through the port I/O2 of the single-chip microcomputer. When K1 is closed, L and L' in B are always on. At this time, the strong power no longer needs to be connected through the strong power button SW1, but K1 will continue to connect to the power supply of household appliances. After the system is stable, lift SW1 (The strong power button SW1 will be lifted quickly after being pressed); when SW1 is pressed and lifted again, the signal is sent to the port I/O1 of the microcontroller. When pressed, it is high level, and when it is lifted, it is a rectangular wave. The I/O2 port of the single-chip microcomputer outputs a low level to control K1 to disconnect, thereby disconnecting L and L' in B to enter the standby zero power consumption state.

The zero-power standby circuit of the present embodiment adopts the photocoupler IC1 to isolate the strong electricity from directly flowing into the single-chip microcomputer C, which ensures the safety of the single-chip microcomputer C and the whole circuit; The connection avoids potential safety hazards and enhances the safety of the circuit.

The above embodiments are only used to illustrate the present invention, but not to limit the present invention. Those of ordinary skill in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all Equivalent technical solutions also belong to the category of the present invention, and the scope of patent protection of the present invention should be defined by the claims.

Claims (4)

1. A zero-power consumption standby circuit, comprising: a single-chip microcomputer, a key detection circuit, and a strong current control circuit, and the single-chip microcomputer is connected with the key detection circuit and the strong current control circuit respectively, and is used to receive the The strong electric button signal, and trigger the strong electric control circuit to control the connection or disconnection of the strong electric and electrical equipment, it is characterized in that, the single-chip microcomputer is connected to the weak electric power supply, and the button detection circuit includes a strong and weak electric isolating device, used In order to isolate the strong current from entering the microcontroller; Wherein, the strong and weak electric isolation device includes a photocoupler, the anode end of the light-emitting diode of the photocoupler is connected to the strong electric button, the cathode end of the light-emitting diode is connected to the neutral line of the strong electricity, and the photosensitive The emitter terminal of the triode is grounded, and the collector terminal of the photosensitive triode is connected to the single-chip microcomputer; Wherein, the strong and weak electrical isolation device further includes: a first resistor, a second resistor, a first diode and a capacitor, and the first resistor, the first diode and the capacitor are connected in parallel to the light emitting diode of the photocoupler. Between the anode terminal and the cathode terminal of the diode, the cathode terminal of the light emitting diode of the photocoupler is connected to the neutral line of strong electricity through the second resistor. 2. The zero-power standby circuit according to claim 1, wherein the button detection circuit also includes a strong power button, the strong power button is connected to the strong and weak current isolation device, and the strong and weak current isolation device is connected to the microcontroller. 3. The zero-power standby circuit according to any one of claims 1 to 2, wherein the strong current control circuit comprises: a control sub-circuit and a relay, and the control sub-circuit is respectively connected to the single-chip microcomputer and the The relay is used to control the on and off of the contact switch of the relay to connect or disconnect the connection between the strong current and the electrical equipment. 4. The zero-power standby circuit according to claim 3, wherein the control sub-circuit comprises: a triode, a third resistor, a fourth resistor and a second diode, and the base of the triode passes through the first Four resistors are connected to the microcontroller, the emitter is grounded, the third resistor is connected between the base and the emitter of the triode, the second diode is connected to both ends of the relay, and the anode is connected to the collector of the triode. The electrode and the cathode are connected to the relay power supply.